Extracting oil from seeds



" either indigestible or Patented July 11, 1933 UNITED STATES BRUNO BEWALD, 0F HAMBURG, GER-[ANY EXTRAGTIHG OIL FROM SEEDS Ho Drawing. Application filed October 24, 1929, Serial No. 408,802, and in Germany early in 1829.

The present invention relates to extracting oil and lecithin from seeds containin the same. Examples of such seeds are soy can, cottonseed, peanuts and the like.

Heretofore the practically universal pressing method commercially employed in the production of oils from such seeds has been to press the same hot in a hydraulic press at very high pressures. This is open to certain objections, in that while the Oll may be in jured only slightly, the residue is substantially injured. These seeds contain cons derable amounts of proteins and the heat which is used in the ressing operation, generally between 80 and '120" (1., is sufficient to repder the proteins far less digestible than 111 the original seeds, so that the subsequent use of the resscake as a food material is myured somewliat. The proteins are in part decom' posed by part hardened sufiiclently to render the same less readily digestible. I may call attention at this point to the fact that the lecithinpresent n such materials exists in two forms therein, artly free and partly as a loose (1. e. easily ecomposable) chemical compound with the proteins. In accordance with the present invention it is desired to remove all of the lecithin from the materiall As a reliminary step, the seeds are preferably ormed into greats, namelysmall slices. Prior to this operation the hulls may be largely removed if desired, by methods already known in the art, or otherwise.

The seeds or the cats are not heated, either before or during the extraction operation, and the extraction is preferably conducted at room temperature.-

The comminuted seed material may be placed in a suitable extraction or leaching device, and a mixture of benzol with 1 to 10% of ethyl or methyl alcohol is allowed to percolate through the mass, until freed from oil to the desired extent. The proportion of the alcohol in the mixture is always low, not over 10% and preferably about 5%. Amounts between about 1% and about 5% can also be used. This concentration of the alcohol does the high temperature and are in,

-or odors to the oi y material or to the ex- -a mount not substantially harden or reduce the (ligestibility of the proteins.

When the extraction has been sufiiciently completed, the remaining solvent mixture is allowed to drain ofi, and the material is dried, for example by being allowed to fall countercurrent through a rising current of warm air or other gas, and in this operation I preferably avoid the use of temperatures higher than 50 to C., or C., at the maximum. Methyl alcohol is superior to ethyl alcohol for use in this process since ithas a better dis'solvin action. Ethyl can however be employed. he composite solvent dissolves out not only the oil but the whole of the lecithin, including the lecithin which is in the free state in the seeds, as well as that which is in the form of a loose combination with the proteins. If benzol were used as the solvent, it would not dissolve out this latter. Methyl alcohol or ethyl alcohol used in the process should of course be pure or should be sufliciently free from impurities that it will not im art objectionable flavors tracted residue. Synthetic methanol is preferrecl.

Ordinarily, I preferably leave one-half to oneper cent of oil in the residue, since the last portions of the oilare'onl removed from the residue with great d' culty and for most purposes it is desired to have a small 0 oil in the residue, when the latter is to be used for feeding purposes.

The leaching or extraction can be carried out in a series of extraction batteries, with the solvent flowing through the series of batteries, cominghinto contact first with the material which as been most completel leached, and coming into contact finally wit fresh material, whereby the quantity of solvent used for leaching will be much reduced.

I have referred above in numerous places to the use of benzol. It will be understood that it is not necessary to use chemically pure benzene and ordinary benzol contains a mixture of nzene, toluene and the like. Toluene, xylene or mlxtures of these or either of these with benzene may be employed in place of the benzol, in the proportions above referred to, that is to say the single-ring aromatic hydrocarbon is in all cases at least 10 to 20 times greater thanthe amount of the lower alcohol.

It will be understood that the solution of oil and lecithin in the composite solvent employed will be subjected to filtration if necessary, and then to distillation to recover the solvent for reuse.

The dried residue of the solid seed mate-- rial can be directly used in cattle feed, or can be ground up to be used for various other purposes.

I claim 1. In the extraction of oil and lecithin from oil-bearing seeds rich in lecithin, the herein described improvement which comprises subjecting the untreated ,seeds, in a comminuted condition to extraction with a composite solvent containing an aromatic hydrocarbon as its largest constituent together with about one to ten per cent of a lower alcohol, and thereafter drying the seed material in a flowing current of gas at not above 70 C.

2. In treating seed material containing oil and lecithin, the step of extracting the same with a composite solvent composed essentially of benzol and a lower alcohol, in the ratio of at least 10:1.

3. In treating seed material containing oil and lecithin, the step of extractin the same with a composite solvent composefessentially of benzol and a lower alcohol, in the ratio of about 20: 1. 1

4. The step of extracting oil from oleaginous seed containing lecithin in both the free and combined state, by treating the same while cold, with a mixture of a single rin aromatic hydrocarbon and a lower alcoho in the proportions of at least 10:1, which extracting liquid is substantially. free from such impurities as would leave permanent odor or taste therefrom in the oil or residue.

5. The step of extracting oil from olea inous seed b treating the same while d, and while t e proteids therein are in their original readily digestible condition, with a mixture of a single ring aromatic hydrocarbon and a lower alcohol, in the pro ortions of at least :1, which extracting iquid is substantially free from such impuritiesas would leave permanent odor or taste therefrom in the oil or residue.

6. In treating seed material containing oil and lecithin, the step of extracting the same while the protein content thereof is still in its original readil digestible condition, with a composite so vent composed essentially of benzol and a lower alcohol, in the ratio of at least 10: 1.

7. In treating seed material containing oil and lecithin, the step of extracting the same while the protein content thereof is still in its original readily digestible condition with a composite solvent com osed essentially of benzol and a lower alcoliol, in the ratio of a about 1.

In testimony whereof I allix my si ature.

BRUNO REwis Ln.

CERTIFICATE OF CORRECTION.

Patent No: 1.91am July n. 1933.

more mum.

- It is hereby certified "that the above numbered patent was erroneously issued to the inventor "Bruno Rewsld", whereas said patent should have been issued to Hansestische Muhlenwcrkc Akticngesellschsft. of Hamburg, Germany. a joint stock company of Germany,

as assignee of the entire interest in said invention, as shown by the records of lssigm ments in this office; and that the said Letters Patent should be read with this correction therein that the some may conform to the record of the case in the Patent Office.

Signed and sealed this 10th day of December, A. D. 1935.

Lesli'b Frazer (Seal) Acting Commissioner of Patents.

referred to, that is to say the single-ring aromatic hydrocarbon is in all cases at least 10 to 20 times greater thanthe amount of the lower alcohol.

It will be understood that the solution of oil and lecithin in the composite solvent employed will be subjected to filtration if necessary, and then to distillation to recover the solvent for reuse.

The dried residue of the solid seed mate-- rial can be directly used in cattle feed, or can be ground up to be used for various other purposes.

I claim 1. In the extraction of oil and lecithin from oil-bearing seeds rich in lecithin, the herein described improvement which comprises subjecting the untreated ,seeds, in a comminuted condition to extraction with a composite solvent containing an aromatic hydrocarbon as its largest constituent together with about one to ten per cent of a lower alcohol, and thereafter drying the seed material in a flowing current of gas at not above 70 C.

2. In treating seed material containing oil and lecithin, the step of extracting the same with a composite solvent composed essentially of benzol and a lower alcohol, in the ratio of at least 10:1.

3. In treating seed material containing oil and lecithin, the step of extractin the same with a composite solvent composefessentially of benzol and a lower alcohol, in the ratio of about 20: 1. 1

4. The step of extracting oil from oleaginous seed containing lecithin in both the free and combined state, by treating the same while cold, with a mixture of a single rin aromatic hydrocarbon and a lower alcoho in the proportions of at least 10:1, which extracting liquid is substantially. free from such impurities as would leave permanent odor or taste therefrom in the oil or residue.

5. The step of extracting oil from olea inous seed b treating the same while d, and while t e proteids therein are in their original readily digestible condition, with a mixture of a single ring aromatic hydrocarbon and a lower alcohol, in the pro ortions of at least :1, which extracting iquid is substantially free from such impuritiesas would leave permanent odor or taste therefrom in the oil or residue.

6. In treating seed material containing oil and lecithin, the step of extracting the same while the protein content thereof is still in its original readil digestible condition, with a composite so vent composed essentially of benzol and a lower alcohol, in the ratio of at least 10: 1.

7. In treating seed material containing oil and lecithin, the step of extracting the same while the protein content thereof is still in its original readily digestible condition with a composite solvent com osed essentially of benzol and a lower alcoliol, in the ratio of a about 1.

In testimony whereof I allix my si ature.

BRUNO REwis Ln.

CERTIFICATE OF CORRECTION.

Patent No: 1.91am July n. 1933.

more mum.

- It is hereby certified "that the above numbered patent was erroneously issued to the inventor "Bruno Rewsld", whereas said patent should have been issued to Hansestische Muhlenwcrkc Akticngesellschsft. of Hamburg, Germany. a joint stock company of Germany,

as assignee of the entire interest in said invention, as shown by the records of lssigm ments in this office; and that the said Letters Patent should be read with this correction therein that the some may conform to the record of the case in the Patent Office.

Signed and sealed this 10th day of December, A. D. 1935.

Lesli'b Frazer (Seal) Acting Commissioner of Patents. 

